M243

This document is a schematic diagram titled "D TYPE FLIP FLOPS M243" for a circuit board identified as M243-0-1.

Key information provided:

• Purpose: The schematic is for test and maintenance purposes, and the circuits are proprietary to Digital Equipment Corporation, copyrighted in 1970.
• Circuit Function: The board implements D-type flip-flops, primarily utilizing four DEC1074H74 integrated circuits and one DEC1074HLQ IC.
• Components: The schematic includes various discrete components such as transistors (DEC30098, DEC2219), diodes (D662, D664, 1N752A), resistors (multiple values from 47Ω to 2.2KΩ), and capacitors (0.01uF disk, 39uF tantalum). L1 and L2 are specified as ferrite beads.
• Power Supply: The circuit operates with multiple voltage rails including +5V, +2.8V, +0.7V, and -15V.
• General Specifications: Unless otherwise indicated, resistors are 1/4W, 5%; disk capacitors are 0.01uF, 100V, 20%; and for all ICs, Pin 7 is Ground and Pin 14 is +5V.
• Parts List: A detailed list enumerates all components, their part numbers, descriptions, and quantities required for the assembly. This includes the main flip-chip handle, etched circuit board, and various electronic components.
• Conversion Chart: A transistor and diode conversion chart is also included.